1 / 15

Forces in the Earth’s Crust Earth Comm : Understanding Your Environment, pages 43-47

Forces in the Earth’s Crust Earth Comm : Understanding Your Environment, pages 43-47. Earth and Space Science. I. Forces in the Earth’s Crust. Natural forces fold, tilt, and move rock layers  These actions are called deformation Can cause layers of rock to be folded, break,

indiya
Download Presentation

Forces in the Earth’s Crust Earth Comm : Understanding Your Environment, pages 43-47

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Forces in the Earth’s CrustEarth Comm: Understanding Your Environment, pages 43-47 Earth and Space Science

  2. I. Forces in the Earth’s Crust • Natural forces fold, tilt, and move rock layers These actions are called deformation • Can cause layers of rock to be folded, break, and move

  3. There are three types of forces that can deform rocks.

  4. 1. Tensional forces – Forces which stretch / pull parts of the rock in opposite directions

  5. 2. Compressional forces – Forces that squeeze together parts of the rock

  6. 3. Shear forces – Forces that try to cause materials to slide past each other

  7. They can act alone or as a combination * If any of these forces are greater than the material’s strength, the material will deform (bend, break, stretch, compress, twist, etc.)

  8. A. Folding and Faulting

  9. Temperature plays a key role as to what type of deformation occurs • Low temperature  rocks are brittle and break easily - deform by fracturing / faulting - generally the rocks in the upper crust are cooler in temperature

  10. Temperature plays a key role as to what type of deformation occurs • High temperature  rocks tend to deform by changing in shape continuously instead of breaking • Generally the rocks in the lower crust are warmer in temperature

  11. Folding is an example of how rocks can change their shape continuously without breaking

  12. Speed of deformation plays a key role if force builds up slowly = folding is more likely if force builds up quickly = faulting is more likely

  13. Fault • A crack in the lithosphere which can allow rock bodies to move past each other can be caused by shear forces, compressional forces, and/or tensional forces or a combination

  14. Folding • A bend in a layer of rock, usually due to deformation - usually caused by compressional forces - very common in layered rocks such as sedimentary

  15. * These processes occur over long periods of time and cannot be directly observed in nature

More Related